ABSTRACT Nipah (NiV) and Hendra (HeV) viruses are highly pathogenic type species of the Henipavirus (HNV) genus within the family Paramyxoviridae. Zoonotic transmission of NiV and HeV from their natural fruit bat reservoirs to humans can result in mortality rates in excess of 90%. In humans, HNVs can cause acute and fatal respiratory disease and encephalitis. Although the exact route of transmission in humans is not known, epidemiological studies and studies in experimental animal models suggest that the respiratory tract is important for virus replication. Importantly, human-to-human transmission was previously reported during outbreaks and NiV could be isolated from respiratory secretions. Currently, our knowledge is still limited on the target cells in the respiratory tract, the immune responses during infection, as well as the molecular mechanisms by which HNVs can cause disease. Our overall goal is to establish and evaluate a human 3D lung microphysiologic organ culture (MHOC) model to study NiV infections of the human lung. Specifically the ability of testing the influence of the respiratory microbiome (RMB) on the course of infections in this model is of great importance, since it has been reported that NiV patients with symptomatic respiratory tract infections were significantly more likely to transmit NiV. Our primary objective is to utilize a human lung 3D MHOC model to develop an in vitro model, which will allow studying the mechanisms of lung-associated pathobiology after infection with NiV. A secondary objective is to study the impact of the lung microbiome on infection. Our hypothesis is that this in vitro reconstituted 3D human lung model will demonstrate its relevance as a novel model to study molecular mechanisms of HNV lung pathology and potentially allow for the evaluation of antiviral therapeutics. To interrogate our driving hypothesis, we propose the following Specific Aims: Specific Aim 1: Investigate progressive NiV infection in the human 3D lung MHOC model. Specific Aim 2: Examine the implications of the human lung microbiome on the course of NiV infection.